Tag Archive: KRBTGT

Jan 03

How Attackers Dump Active Directory Database Credentials

I previously posted some information on dumping AD database credentials before in a couple of posts: “How Attackers Pull the Active Directory Database (NTDS.dit) from a Domain Controller” and “Attack Methods for Gaining Domain Admin Rights in Active Directory“. This post covers many different ways that an attacker can dump credentials from Active Directory, both …

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Nov 17

How Attackers Use Kerberos Silver Tickets to Exploit Systems

Usually Golden Tickets (forged Kerberos TGTs) get all the press, but this post is about Silver Tickets and how attackers use them to exploit systems. I have talked about how Silver Tickets can be used to persist and even re-exploit an Active Directory enterprise in presentations at security conferences this year. This post continues this …

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Aug 07

Kerberos Golden Tickets are Now More Golden

At my talk at Black Hat USA 2015, I highlighted new Golden Ticket capability in Mimikatz (“Enhanced Golden Tickets”). This post provides additional detailed on “enhanced” Golden Tickets. Over the past few months, I researched how SID History can be abused in modern enterprises. As part of this research, I reached out to Benjamin Delpy, …

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Feb 18

Interesting KRBTGT Password Reset Behavior

Following up on Twitter conversations (@passingthehash, @scriptjunkie1, gentilkiwi, etc) on the new KRBTGT Password Reset Script and Skip Duckwall’s (@passingthehash) blog post on how KRBTGT password changes work. Microsoft KB2549833 states that the KRBTGT password is set automatically to a random string when a new password is entered. This occurs because there is special logic …

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Nov 10

Kerberos & KRBTGT: Active Directory’s Domain Kerberos Service Account

Every Domain Controller in an Active Directory domain runs a KDC (Kerberos Distribution Center) service which handles all Kerberos ticket requests. AD uses the KRBTGT account in the AD domain for Kerberos tickets. The KRBTGT account is one that has been lurking in your Active Directory environment since it was first stood up. Each Active …

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Sep 12

Kerberos, Active Directory’s Secret Decoder Ring

Kerberos Overview Kerberos is a protocol with roots in MIT named after the three-headed dog, Cerberus. Named because there are 3 parties: the client, the resource server, and a 3rd party (the Key Distribution Center, KDC). Kerberos can be a difficult authentication protocol to describe, so I will attempt to simplify it as best as …

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